An open hose clamp is known from U.S. Pat. No. 4,299,012. There, an ear-shaped tightening means has the purpose of holding the clamp in that tightened condition which is given the clamp when it is mounted on the object to be clamped.
U.S. Pat. No. 4,053,985 discloses an open hose clamp in which the end sections of a clamping band are provided with toothed areas for mutual engagement in the overlapping condition. A clip, which is not explained in detail, has the function of holding the end portions in mutual engagement. Such a clip is known from U.S. Pat. No. 3,078,532. U.S. Pat. No. 1,804,725 describes another hose clamp in which a first toothed area provided at the outer side of a tongue co-operates with a second toothed area provided at the inner side of a raised portion. All these hose clamps with tooth engagement can be tightened when mounted by pulling the free outer end of the clamping band.